It is useful for saving time writing algorithms and common tasks. And because of the site's goal of having many languages, it has many snippets even for uncommon languages like Icon and J.

Example

Need to factor primes in scala?

Create a new file and set language to scala. Or open an existing file.

Select "Rosetta Code" in the "tools" menu. Or use the command pallet.

Search for "prime" in the menu, select "prime decomposition"

A 33 line scala prime factorizer appears in the file!

What it does

When invoked, it detects the current file language and pops up a search menu of all the Rosetta Code tasks implemented in that language. When a task is selected it is inserted into the current document.